[1] Capital Med Univ, Beijing Tiantan Hosp, Dept Neurosurg, 6 Tiantan Xili, Beijing 100050, Peoples R China
[2] China Natl Clin Res Ctr Neurol Dis, Beijing, Peoples R China
[3] Beijing Inst Brain Disorder, Ctr Stroke, Beijing, Peoples R China
[4] Johns Hopkins Univ, Sch Med, Dept Neurosurg, Baltimore, MD 21205 USA